This invention relates to a heat exchanger typically used in an automobile air conditioner and, in particular, to a pipe connecting structure included in the heat exchanger.
Recently, various heat exchangers have been developed and used in the automobile air conditioner. A typical one of the heat exchangers comprises a tank portion for defining fluid paths therein and a pipe connecting structure for connecting a fluid inlet pipe and a fluid outlet pipe with the tank portion to communicate with the fluid paths, respectively. The fluid inlet pipe is used for introducing a heat exchange medium into the tank portion. The fluid outlet pipe is used for discharging the heat exchange medium from the tank portion. The heat exchange medium serves as a working fluid while flowing through the fluid paths of the tank portion.
Referring to FIG. 1, description will be made as regards a heat exchanger in a related art. In FIG. 1, the heat exchanger is, for example, mounted in a vehicle and comprises a flange depicted at 101. The flange 101 is made of a single block body with cutting the block body to have an inlet portion 103 and an outlet portion 104 formed integral therewith. The flange 101 is fixed by brazing to a tank portion 102 through a flange stay 108. The tank portion 102 defines fluid inlet and fluid outlet paths 105 and 106 for conducting a heat exchange medium which may be a refrigerant known in the art. Ends of the inlet portion 103 and the outlet portion 104 are slightly inserted in the fluid inlet path 105 and the fluid outlet path 106 to communicate therewith, respectively. The other ends of the inlet portion 103 and the outlet portion 104 are for being connected with a fluid outlet pipe and a fluid inlet pipe which are not shown in FIG. 1. It is to be noted that the flange 101 is provided with a threaded hole 107 to engage a screw (not shown) used for fixing, for example, an expansion valve which is included in a cooling circuit known in the art.
Inasmuch as the flange 101 is made of the block body, i.e., an unhollow or solid member, it may be difficult to fully meet the demand for reduction in weight of the heat exchanger in order to improve the fuel efficiency. In addition, an increase in temperature will be insufficient upon brazing of the flange 101 to the tank portion 102 because the flange 101 is great in heat capacity. This may result in defective brazing.
In order to fabricate the flange 101, such single block body is subjected to cutting to form the inlet and the outlet portions 103 and 104. Therefore, it is difficult to reduce the material cost and the production cost. As a consequence, it would be impossible to achieve the reduction in cost of the heat exchanger using the flange 101 or an air conditioning apparatus using the heat exchanger.
It is therefore an object of this invention to provide a heat exchanger which is considerably reduced in weight and cost.
It is another object of this invention to provide a heat exchanger of the type described, which is improved in reliability and efficiency of brazing.
Other objects of the present invention will become clear as the description proceeds.
According to an aspect of the present invention, there is provided a heat exchanger which comprises a tank portion defining a fluid inlet path and a fluid outlet path for conducting a heat exchange medium, an inlet portion formed integral with said tank portion to communicate with said fluid inlet path, said inlet portion being adapted to connect with a fluid inlet pipe which is for introducing said heat exchange medium into said fluid inlet path, and an outlet portion formed integral with said tank portion to communicate with said fluid outlet path, said outlet portion being adapted to connect with a fluid outlet pipe which is for discharging said heat exchange medium from said fluid outlet path.
According to another aspect of the present invention, there is provided a heat exchanger which comprises a tank portion defining a fluid inlet path and a fluid outlet path for conducting a heat exchange medium, an inlet portion formed integral with said tank portion to communicate with said fluid inlet path, said inlet portion being adapted to connect with a fluid inlet pipe which is for introducing said heat exchange medium into said fluid inlet path, an outlet portion formed integral with said tank portion to communicate with said fluid outlet path, said outlet portion being adapted to connect with a fluid outlet pipe which is for discharging said heat exchange medium from said fluid outlet path, and a flange plate coupled to said inlet portion and said outlet portion for supporting said fluid inlet pipe and said fluid outlet pipe.
According to still another aspect of the present invention, there is provided a heat exchanger which comprises a tank portion defining a fluid inlet path and a fluid outlet path for conducting a heat exchange medium, an inlet portion formed integral with said tank portion to communicate with said fluid inlet path, said inlet portion being adapted to connect with a fluid inlet pipe which is for introducing said heat exchange medium into said fluid inlet path, an outlet portion formed integral with said tank portion to communicate with said fluid outlet path, said outlet portion being adapted to connect with a fluid outlet pipe which is for discharging said heat exchange medium from said fluid outlet path, a flange plate coupled to said inlet portion and said outlet portion for supporting said fluid inlet pipe and said fluid outlet pipe, and a flange stay placed between said flange plate and said tank portion, said flange plate being connected to said tank through said flange stay.